Novel mutations in the calcium sensing receptor gene in tropical chronic pancreatitis in India.
Tropical chronic pancreatitis (TCP) is a form of chronic pancreatitis seen in many tropical countries in young non-alcoholic subjects who are often malnourished. Nutritional deficiencies, either at the macro or micro level, and food toxins have been implicated in its causation, although there is no final proof to confirm this suggestion. Mutations of SPINK1 and CFTR genes have been proposed as disease modifiers, or as determinants of phenotypes. Mutations involving the calcium sensing receptor (CASR) have been suggested to increase the risk of chronic pancreatitis (CP), since high intracellular levels of calcium activate trypsinogen within the acinar cells. A combination of CASR and SPINK1 gene mutations has been proposed to predispose to idiopathic CP. The purpose of this study was to report on novel mutations in CASR, identified in TCP patients.



We screened our TCP patients for mutations in CASR and SPINK1 genes. In a cohort of 35 patients and an equivalent number of controls, genomic DNA was screened for mutations in CASR and SPINK1 by direct DNA sequencing.



Four new mutations were found in the CASR gene. A combination of both SPINK1 (N34S) and CASR mutations was seen in 6% of the patients, while 22% harbored a single mutation.



Our study suggests, for the first time, that CASR mutation may be a risk for TCP, and that this risk may be further increased if there is an associated SPINK1 mutation.
Murugaian
Elango E
EE
Department of Molecular Biology, Amrita Institute of Medical Sciences and Research Center, Cochin, Kerala, India. elango@aims.amrita.edu
Ram Kumar
Ram Mohan
RM
Radhakrishnan
Lakshmi
L
Vallath
Balakrishnan
B
D000293:Adolescent; D000328:Adult; D002352:Carrier Proteins / Q000235:genetics; D002648:Child; D005260:Female; D006801:Humans; D007194:India; D008297:Male; D009154:Mutation; D050500:Pancreatitis, Chronic / Q000235:genetics*; D044169:Receptors, Calcium-Sensing / Q000235:genetics*; D014359:Trypsin Inhibitor, Kazal Pancreatic
D002352:Carrier Proteins; D044169:Receptors, Calcium-Sensing; C486642:SPINK1 protein, human; D014359:Trypsin Inhibitor, Kazal Pancreatic